 /*******************************************************************************
  * Copyright (c) 2004, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.runtime.content;

 import java.io.*;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.QualifiedName;
 import org.eclipse.core.runtime.preferences.IScopeContext;

 /**
  * Content types represent and provide information on file types, such as
  * associated file names/extensions, default charset, etc.
  * <p>
  * This interface is not intended to be implemented by clients.
  * </p>
  *
  * @since 3.0
  */
 public interface IContentType extends IContentTypeSettings {
     /**
      * File spec type flag constant, indicating that pre-defined file
      * specifications should not be taken into account.
      */
     public static final int IGNORE_PRE_DEFINED = 0x01;
     /**
      * File spec type flag constant, indicating that user-defined file
      * specifications should not be taken into account.
      */
     public static final int IGNORE_USER_DEFINED = 0x02;
     /**
      * File spec type constant, indicating a file name specification.
      */
     public static final int FILE_NAME_SPEC = 0x04;
     /**
      * File spec type constant, indicating a file extension specification.
      */
     public static final int FILE_EXTENSION_SPEC = 0x08;

     /**
      * Returns a reference to this content type's base type. If this content type
      * does not have a base type (it is a root type), returns <code>null</code>.
      *
      * @return this content type's base type, or <code>null</code>
      */
     public IContentType getBaseType();

     /**
      * Returns the default content description for this content type. A default
      * content description is returned by the content type API whenever
      * content analysis could not find any particular information to be described
      * about the contents being processed, so all default attributes for the
      * content type in question apply.
      * <p>
      * Clients doing caching of content descriptions may choose to treat default
      * descriptions in a special manner, since they are easily recoverable
      * through this API.
      * </p>
      *
      * @return a content description
      * @since 3.1
      */
     public IContentDescription getDefaultDescription();

     /**
      * Tries to obtain a description for the given contents.
      * <p>
      * Any IOExceptions that may occur while reading the given input stream
      * will flow to the caller. The input stream will not be closed by this
      * operation.
      * </p>
      *
      * @param contents the contents to be interpreted
      * @param options an array of keys for all properties that should be described
      * @return a content description if one could be obtained, or
      * <code>null</code>
      * @throws IOException if an error occurs while reading the contents
      * @see IContentDescription
      */
     public IContentDescription getDescriptionFor(InputStream contents, QualifiedName[] options) throws IOException;

     /**
      * Tries to obtain a description for the given contents.
      * <p>
      * Any IOExceptions that may occur while reading the given reader
      * will flow to the caller. The reader will not be closed by this
      * operation.
      * </p>
      *
      * @param contents the contents to be interpreted
      * @param options an array of keys for all properties that should be described
      * @return a content description if one could be obtained, or
      * <code>null</code>
      * @throws UnsupportedOperationException if this content type
      * has a describer that does not implement
      * <code>ITextContentDescriber</code>
      * @throws IOException if an error occurs while reading the contents
      * @see IContentDescription
      */
     public IContentDescription getDescriptionFor(Reader contents, QualifiedName[] options) throws IOException;

     /**
      * Returns the default charset for this content type if one has been defined,
      * <code>null</code> otherwise.
      * This refinement of the corresponding <code>IContentTypeSettings</code>
      * method also takes into account the charset defined by the content type
      * provider (or its base content type).
      *
      * @return the default charset, or <code>null</code>
      */
     public String getDefaultCharset();

     /**
      * Returns file specifications from this content type. The type mask
      * is a bit-wise or of file specification type constants indicating the
      * file specification types of interest.
      * This refinement of the corresponding <code>IContentTypeSettings</code>
      * method supports additional flags because it also takes into account the
      * file specifications defined by the content type provider (or its base
      * content type).
      *
      * @param type a bit-wise or of file specification type constants. Valid
      * flags are:
      *<ul>
      *<li>one of <code>FILE_EXTENSION_SPEC</code> or
      *<code>FILE_NAME_SPEC</code></li>
      *<li>and optionally, one of <code>IGNORE_PRE_DEFINED</code>
      *or <code>IGNORE_USER_DEFINED</code></li>
      *</ul>
      * @return the file specification
      * @see #FILE_NAME_SPEC
      * @see #FILE_EXTENSION_SPEC
      * @see #IGNORE_PRE_DEFINED
      * @see #IGNORE_USER_DEFINED
      */
     public String [] getFileSpecs(int type);

     /**
      * Returns this content type's unique identifier. Each content type has an
      * identifier by which they can be retrieved from the content type catalog.
      *
      * @return this content type's unique identifier
      */
     public String getId();

     /**
      * Returns a user-friendly name for this content type.
      *
      * @return this content type's name
      */
     public String getName();

     /**
      * Returns whether this content type is associated with the
      * given file name.
      *
      * @param fileName the file name
      * @return <code>true</code> if this content type is associated with
      * the given file name, <code>false</code> otherwise
      * @see #isAssociatedWith(String, IScopeContext)
      */
     public boolean isAssociatedWith(String fileName);

     /**
      * Returns whether this content type is associated with the
      * given file name in the given preference scope.
      *
      * @param fileName the file name
      * @param context a preference scope context
      * @return <code>true</code> if this content type is associated with
      * the given file name, <code>false</code> otherwise
      * @since 3.1
      */
     public boolean isAssociatedWith(String fileName, IScopeContext context);

     /**
      * Returns whether this content type is a kind of the given content
      * type. A content type A is a kind of a content type B if:
      * <ol>
      * <li>A and B are the same content type, or</li>
      * <li>A's base type is B, or</li>
      * <li>A's base type is a kind of B.</li>
      * </ol>
      *
      * @param another a content type
      * @return <code>true</code> if this content type is a kind of the
      * given content type, <code>false</code> otherwise
      */
     public boolean isKindOf(IContentType another);

     /**
      * Returns the settings for this content type in the given
      * preference context.
      *
      * @param context a preference scope context
      * @return setting in the given context
      * @throws CoreException if this method fails. Reasons include:
      * <ul>
      * <li> An error occurred obtaining the settings.</li>
      * </ul>
      * @since 3.1
      */
     public IContentTypeSettings getSettings(IScopeContext context) throws CoreException;
 }

